RESUMEN
Until vaccines and effective therapeutics become available, the practical solution to transit safely out of the current coronavirus disease 19 (CoVID-19) lockdown may include the implementation of an effective testing, tracing and tracking system. However, this requires a reliable and clinically validated diagnostic platform for the sensitive and specific identification of SARS-CoV-2. Here, we report on the development of a de novo, high-resolution and comparative genomics guided reverse-transcribed loop-mediated isothermal amplification (LAMP) assay. To further enhance the assay performance and to remove any subjectivity associated with operator interpretation of results, we engineered a novel hand-held smart diagnostic device. The robust diagnostic device was further furnished with automated image acquisition and processing algorithms and the collated data was processed through artificial intelligence (AI) pipelines to further reduce the assay run time and the subjectivity of the colorimetric LAMP detection. This advanced AI algorithm-implemented LAMP (ai-LAMP) assay, targeting the RNA-dependent RNA polymerase gene, showed high analytical sensitivity and specificity for SARS-CoV-2. A total of ~200 coronavirus disease (CoVID-19)-suspected NHS patient samples were tested using the platform and it was shown to be reliable, highly specific and significantly more sensitive than the current gold standard qRT-PCR. Therefore, this system could provide an efficient and cost-effective platform to detect SARS-CoV-2 in resource-limited laboratories.
Asunto(s)
Inteligencia Artificial , Betacoronavirus/aislamiento & purificación , Infecciones por Coronavirus/virología , Técnicas de Diagnóstico Molecular/métodos , Técnicas de Amplificación de Ácido Nucleico/métodos , Neumonía Viral/virología , Animales , COVID-19 , Prueba de COVID-19 , Chlorocebus aethiops , Técnicas de Laboratorio Clínico/métodos , Infecciones por Coronavirus/diagnóstico , Perros , Humanos , Células de Riñón Canino Madin Darby , Pandemias , Neumonía Viral/diagnóstico , ARN Viral/genética , Reacción en Cadena en Tiempo Real de la Polimerasa , SARS-CoV-2 , Sensibilidad y Especificidad , Células VeroRESUMEN
Both carotid and intracranial chemoreceptors are critical to a normal ventilatory CO2-H+ chemosensitivity. At low levels of hypercapnia, the carotid contribution is probably greater than the central contribution but, at high levels, the intracranial chemoreceptors are dominant. The carotid chemoreceptors are also critical to maintaining a stable and normal eupneic PaCO2, but lesion-induced attenuation of intracranial CO2-H+ chemosensitivity does not consistently alter eupneic PaCO2. A major unanswered question is why do intracranial chemoreceptors in carotid body denervation (CBD) animals tolerate an acidosis during eupnea which prior to CBD elicits a marked increase in breathing.
Asunto(s)
Dióxido de Carbono/fisiología , Cuerpo Carotídeo/fisiología , Células Quimiorreceptoras/fisiología , Hipercapnia/fisiopatología , Fenómenos Fisiológicos Respiratorios , Animales , Encéfalo/fisiología , Cuerpo Carotídeo/fisiopatología , Humanos , Modelos AnimalesRESUMEN
The Insulin/IGF-like signalling (IIS) pathway plays an evolutionarily conserved role in ageing. In model organisms reduced IIS extends lifespan and ameliorates some forms of functional senescence. However, little is known about IIS in nervous system ageing and behavioural senescence. To investigate this role in Drosophila melanogaster, we measured the effect of reduced IIS on senescence of two locomotor behaviours, negative geotaxis and exploratory walking. Two long-lived fly models with systemic IIS reductions (daGAL4/UAS-InRDN (ubiquitous expression of a dominant negative insulin receptor) and d2GAL/UAS-rpr (ablation of insulin-like peptide producing cells)) showed an amelioration of negative geotaxis senescence similar to that previously reported for the long-lived IIS mutant chico. In contrast, exploratory walking in daGAL4/UAS-InRDN and d2GAL/UAS-rpr flies declined with age similarly to controls. To determine the contribution of IIS in the nervous system to these altered senescence patterns and lifespan, the InRDN was targeted to neurons (elavGAL4/UAS-InRDN), which resulted in extension of lifespan in females, normal negative geotaxis senescence in males and females, and detrimental effects on age-specific exploratory walking behaviour in males and females. These data indicate that the Drosophila insulin receptor independently modulates lifespan and age-specific function of different types of locomotor behaviour. The data suggest that ameliorated negative geotaxis senescence of long-lived flies with systemic IIS reductions is due to ageing related effects of reduced IIS outside the nervous system. The lifespan extension and coincident detrimental or neutral effects on locomotor function with a neuron specific reduction (elavGAL4/UAS-InRDN) indicates that reduced IIS is not beneficial to the neural circuitry underlying the behaviours despite increasing lifespan.